Dr. Stein has just invested $10,000 for his son (age 7). The money will be used for his son's education 10 years from now. He calculates that he will need $21,598 for his son's education by the time the boy goes to school. What rate of return will Dr. Stein need to achieve this goal? Choose the closest answer.

A) 10%

B) 8%

C )4%

D) 1%